unity freeze while using only tilemap

Hi,
Im sorry my english is very bad but i already asked many people nobody could help.

I have a huge error on my unity (2019.2.8f1 64 bit) it freeze when i use "too many" tilemap.
when i say freeze i mean i can't do anything in the editor (like clic a button) or it work 10 minutes later...
And its only unity if i want to do something else on the pc like photoshop or zbrush i dont have any problem.

This is a screen of my scene :

On this point it work well but if i try to do all the background unity freeze i dont use script or anything only tilemap.
And i dont have anything in the console.


i followed this tutorial :

My config is :
Ram = 16 Go
µp = 4.0Ghz 8 Core
Graphic card = Amd Radeon R9 390 Oc 8go DDR5

Thanks for your help and your time.

 

Are you sure Unity uses your GPU? By default, Unity uses the integrated graphics unless you instruct your computer to use the GPU when you start Unity.